(1) _What_ is Nature? = What are the facts which constitute Nature. (Knowledge of Nature). (2) _How_ has Nature come to be what she is? = How is it that facts constituting Nature have become as we perceive them? (Explanation of Nature). (3) _Why_ is Nature as she is and not otherwise? = Why is it that facts constituting Nature have a certain uniformity (order) continuity and unity in spite of changes that take place continuously? (Reason of Nature). Broadly speaking, I may say that Science (with its various departments called "Sciences") tries to answer the first question _what_, the question as to _facts_ of Nature. Philosophy tries to answer the second question _how_, the question as to the _explanation_ of Nature. Religion or Theology (which includes highest Poetry) tries to answer the third and last question _why_, the question as to the _reason_ of Nature. You may thus clearly remember the respective provinces of Science, Philosophy and Religion by remembering three words What, How and Why. When you read a book which treats of facts or the _what_ of Nature; or of the explanation or the _how_ of her; or of the reason or the _why_ of her; you may be sure it is Science, Philosophy or Religion respectively that you are reading, whatever be the name of the book itself. I have said that Science, Philosophy or Religion "_tries_ to answer" and not "answers", because the answer of any of them can never be final or immutable. None of them can ever reach finality. As the experience of mankind grows continuously, new facts or new phases of old facts are discovered in the course of time. Just as men have to adapt or adjust themselves to new facts (or to changes in old facts) or else die; so men's Science, Philosophy and Theology have to adjust themselves to new facts or else become empty nothings.[85] II. I have often said that I believe Islam to be the best religion because (so far as I know) it accords best with the current ideas of Science. If you accept my view of the respective provinces of Science, Philosophy, and Religion, you can easily comprehend that a Religion like Islam which purports to expound the reason _why_ of Nature must needs correspond with the _what_ (Science) as well as with the _how_ (Philosophy) of Nature. The three great divisions of Human Thought--I mean, Science, Philosophy and Religion--are necessarily connected with one another, as otherwise they cannot make up _the whole Universe of Human Thought_ and cannot satisfy men's craving for complete and consistent knowledge. III.