Biases:
Aristotle - everything in nature must have a purpose, (extends to organs)
Purpose: To prove that there is a one-way valve in the ureter that disallows urine from flowing upwards towards from the bladder to the kidneys.
*First, blocks both ureters,.
-Observes the ureters swell with urine while the bladder remains empty
*Second, blocks the urethra, then removes blocks from ureters.
-Observes that the bladder fills up.
-Upon being squeezed the urined does not flow back 'north' towards the kidneys.
*Finally, blocks ONLY ONE ureter
-Notes that the blocked one becomes destended, while the unblocked functions normally (remains flaccid).
Procedural notes:
Galen emphasizes that the experiment is repeatable, with consistent results. "If anyone will but test this for himself on an animal, he will condemn the errors [of others] and learn also the [true] reason. . ."
The conclusion is experimentally based, and repeatable. Staight up good science. Also, that the procedure is reversible.
Galen tested urine flow of sheep. In his experiment he blocked certain paths in the urines flow. When both the ureters were blocked, the area behind the blockage there was bloating after the kidneys and before the blockage. When there was blockage in after the bladder the bladder became bloated but not the same area befure in the ureters. Galen concluded that flow did not go backwards towards the kidneys or the bladder when blocked. He assumed in this experiment that the kidney was the start and the penis was end. He also assumed that bloating was because of the blockage. We believe that he conducted 3 different experiments to prove his hypothesis.
Galen began with the assumptions that "every part of the body is so constructed as best to perform a predetermined function" and that the function of the urinary tract is to prevent urine from flowing back into the kidneys.
In order to test this second assumption he performed his experiment of blocking different parts of the urinary tract on both dead and living animals and tested all possible combinations of the three tubes (e.g. blocking one of the two ureters, then both, and the urethra). He also observed and recorded all of the consequences of his different actions. This was his methodology to isolate which actions (factors) lead to certain results.
Galen concludes, based on his observations of his experiment, that his second assumption regarding the inability of the urine to flow back into the kidneys, ureters and bladder, once it has passed into a new section is correct.
He tested his hypothesis on sheep to prove that their are one way valves on the ureters and above the urethra that only allow urine to flow down and not overflow the kidneys. He concludes that if all people perform this test on animals for themselves and have the same results, then that proves the truth in his hypothesis. This is valid suggestion because it would be a scientific method that would be more accurate than only one person performing the test.
Galen performs an inhumane experiment on a sheep, and through a strictly experimental process to demonstrate and validate the idea that urine always flows south.
Before he begins the experiment, Galen seems to have a few predetermined notions, although open to experimenting and verifying. One such assumption that Galen carried was in line with the Aristotelian view that all things, and specifically the body parts of animals and human beings, carried predetermined purposes and functions. According to the text, this idea was consistent with the common Arabian and Christian theologies of the day and were a large factor in his acceptance in the scientific community of the day.
The first step Galen performed in the experiment was, through the employment of ligatures, the closure of both of the ureters on the sheep in question. This then led to the ureter swelling with the fluid and, in the words of Galen, became "quite full and distended - in fact almost to the point of rupturing."
The next step involved removing the blockages from the ureters and in turn tying a ligature around the penis of the sheep, in order to block the urethra. The consequent stoppage caused the bladder of the sheep to swell, and thus involved a different part of the flow of the urine.
He then blocked individual ureters and demonstrated to himself and the scientific community that if one ureter were blocked, only that ureter's flow would be affected.
He concludes by stating that the flow of urine continuously goes "south", and that the one-way process of the fluid is irreversible. He finally states that, "if anyone will but test this for himself on an animal, he will condemn the errors and learn also the reason." The assumption we have made from this is that his claims were potentially refuting other widely accepted scientific theorems of the time.
Galen is hypothesizing that the flow of urine in sheep goes South; by making this hypothesis, he assumes that he is correct (which he hopes his experiment will ultimately demonstrate). He also assumes that his experiment relates to humans, and that the urinary tract of a sheep can be compared to a human (at least, we assume so). His methods are as follows: he tests the presence of one-way valves by creating blockages at different crucial points throughout the urinary tract (ureters, urethra). The fact that at each blockage the urine flow does not go backwards is what he cites as proof that there exists one way valves in the urinary tracts of sheep, at that urine only flows south. He notes this pattern in both dead and live sheep.
In Galen's experiment with the sheep has three major parts, assumptions, methods and conclusions, which is similar to the scientific method.
First, his assumptions are few and barely affect his experiment. Two of his major assumptions are that "everything in nature has a purpose" and that there is a "[true] reason".
Next, his experiment (method) involved both alive and dead sheep and their urinary tract. The first thing he did was block both ureters coming from the kidneys. The ureters, after some time, became bloated, but not the kidney's themselves. Then he unblocked both ureters and they emptied into the bladder and then out of the sheep. Next, he blocked the urethra, and noticed that the bladder became bloated by not the urter or kidneys. He then unblocked the urethra and blocked the left ureter. He then noticed that the left ureter bloated, but not the left kidney, bladder, or left ureter and kidney. This what the entirety of the his experiment. Remember that he did this one both alive and dead sheep.
Galen concluded the "irreversibility of the flow of urine from the badder 'south'". Also, he concluded that if anyone else did the same test as himself, they will "condemn" the errors of others.
Galen first assumes that the bowel system is a one way track. He blocks various parts of the urinary track in order to test his hypothesis. No matter full the badder gets, Galen finds that the urine never travels backwards in the urinary track (just like he hypothesized). Through this he successfully proved that the urinary track only flows in one direction.
The assumption is that, for the process of urination, there are one way valves that prevent urine from retreating back into a previous organ, once it had travelled through a valve. This assumption is clearly defined and testable which he did by blocking the ureters with ligatures and waited - the results showed that the bladder was empty but that the ureters had expanded almost to the point of rupturing. He then took the ligatures off the ureters and put a ligature on the penis, blocking the bladder. He saw that the bladder filled almost to the point of rupturing but that the ureters were empty. He squeezed the bladder but nothing went back up into the ureters and kidneys. Therefore he was able to conclude that there are in fact one way valves between the kidneys and ureters, and the ureters and bladder.
Galens method involves expirementing on the urinary tract of sheep. His basic assumption is that every part of the body has a function and that through experimentation humans can understand its purpose. He blocked different areas with ligatures to see if his findings were consistent. He recorded the data he collected and used it to prove his theory that the urinary tract has one way valves. Galen's work is real science because his expirements can be repeated. He says, "Now if anyone will but test this for himself on an animal, he will condemn the errors [of others] and learn also the [true] reason".
Kimberly Leyerly
Shannon McClory
Ashley Buchholz
Brenna Houch
Galen believes that the body is constructed in the best way to perform its intended purpose. His method was forming a hypothesis that the body has something that prevent urine from traveling backwards that he then tested by blocking a sheep's ureter, then observed the consequences of the blockages and finally analyzed the results of his experiment. Galen concluded that his original hypothesis was correct when he found that there were one-way valves that prevented the traveling of urine back into the kidneys or ureters. This was a thorough demonstration of how Galen was a true experimental scientist.
Assumptions: every part of body is constructed as best to perform a predetermined function. Religious beliefs consistent with Christian and Arab theology. The sheep he tested had normal functioning body parts and were not different from other sheep in a way which would have skewed his results.
Hypothesis: urine flows from the kidneys to the bladder, and will not flow back to the kidney even when the bladder is blocked.
His experiment proved the urine wouldn't back up, but as he wasn't able to see inside the animal it didn't prove the existance of a valve. However, a similar mechanism was proved regardless, and thus his statement of "the ureters are prevented from recieving back the urine from the bladder" was correct.
Galen's hypothesis is that the flow of urine is irreversible from the "south" back into the kidneys. Galen systematically plugged different tubes within his subject to test his assumptions about urine's one way flow. Galen concluded that no matter if the animal is live or dead you can observe and conclude yourself that urine flows only one way due to one way valves in the urinary tract.
Hypothesis/Assumptions: Urine flows one way.
Methodology: Systematically clamp ligatures around different parts of test subject's urinary tract. Observe with both live and dead animals, checking to see if urine retracts and develops distended kidneys, ureters, or bladder.
Conclusion: Urine flows one way throughout entire system.
Galen uses the method of tying ligatures on to different areas of the sheep's urinary tract system to understand how the passages of the tract work; and whether or not they are one way or two way tracts. He tests constricting the different passages, such as the Ureters, the bladder and the Urethra in different, methodical combinations to determine which areas are stressed, and what occurs when one or more passages are blocked. Galen preseneed the hypothesis that the flow of urine from the bladder is irreversable- urine flows in one direction. This is a good example of an individual actually physically testing an idea.Galen goes on to illustrate how the test was run, and states that anyone could do the same and observe the same results. In that vein, Galen's methodology reflects the first deliberate practice of the scientific method.