Even before we had any concrete proof of anything, ancient philosophers still made hypotheses about heredity. The two major people being Hippocrates and Aristotle. Hippocrates’ theory was that the material for heredity is made up of physical materials His proposal was that all the parts of the body came together in a man’s seed and formed into a human being inside the womb. The idea was classified as a “brick and mortar” theory. Another belief of his was the idea of inheritance of acquired characteristics. His idea was that an Olympic runner’s strong leg muscles result in more ‘leg muscle parts’ in the man. But some time later, Aristotle criticized Hippocrates’ theory. The first objection he had to it was that mutilated and physically handicapped people could still have a normal child. The second objection made was that people can transmit characteristics that they don’t show at a young age, but do at an older age. For example, gray hair or pattern baldness in men. When people are young they don’t exhibit gray hair or pattern baldness. Hence, there are no parts for gray hair and pattern baldness, but those parts possibly become available later in life. That obviously doesn’t make sense because parents can still transmit those traits to their offspring. Aristotle’s third and final objection was that of the bricks and mortar model for heredity transmission. His alternative was that heredity involved the transmission of information. this model was called the “Blueprint Model”. It would seem that Aristotle’s model makes more sense, but all subsequent theories were based off of the bricks and mortar model. It wasn’t until the mid 20th century that Aristotle’s astounding insight was recognized.