Aristotle was the greatest philosopher who ever lived. Many of his ideas have been grossly misinterpreted by people who have assumed that because he lived twenty three centuries ago he must have been stupid. This is a mistake. Many ideas of Aristotle's are deeply subtle and those who assume he was ignorant of modern science and therefore cannot be expected to have got anything right are never going to understand him. This is a position tantamount to an assertion that there is absolute truth, and that modern physics and modern biology is it. This is a terrible mistake. There is indeed an absolute truth, and Aristotle's formal logic and scientific method will find it. But modern science is not it. Modern science is wrong because it is based on the assumption that one can explain phenomena by reducing them to the properties inherent in some basic building blocks, typically atoms, molecules, or some fundamental particle or other, depending on how sophisticated is the proponent of the view. But this is manifestly not true as anyone who reads even a little of the literature on the interpretation of quantum mechanics will find. The deep mysteries of quantum mechanics are simply a consequence of the failure to understand that a whole system may have essential properties, such as angular momentum for example, which are not reducible to inherent properties of its constituent parts.
Here is a collection of some of his works, translations of which are now in the public domain in Works of Aristotle. It is not yet complete. I am working on an index and adding other works which have been neglected or are considered not part of the corpus.
Here is an introduction to Aristotelian logic that I wrote. And here is a dialogue between Aristotle, a reincarnated Charles Dodgson, his girlfriend and Che Guevara, illustrating some of the more outrageous clashes between modern physics and logic.