Your analogy between Evolution and Gravity is a good one, but I don't think you're using it correctly.
This is how I see the analogy lining up:
Idea - Gravity
Basic Description - Objects with mass attract one another
Reason - ??
Idea - Evolution
Basic Description - The change in biological species over generations due to imperfect reproduction
Reason - ??
MrQ writes:
Asteroid doesn't hit the earth not because it chooses to hit the earth. But everything in universe has reason behind it. The reason for asteroid hitting the earth is gravity. You remove that and no asteroid will even bother coming this way!
What you said - Reason for asteroid hitting the earth = Gravity
Analogy - Reason for having different species in different environments = Evolution
But, as you see, this does not give us a reason for having Gravity as it equally does not give us a reason for having Evolution.
If you think there is a reason for Gravity, please explain:
What is the purpose behind having objects with mass attract one another?
Science cannot answer this question either. We can explain
how objects with mass attract one another with some very precise equations. But, objectively (scientifically), asking why this is so doesn't make any sense. Purpose is a subjective idea created by the human imagination. You can't expect the natural world to conform to human imagination.
Everything that happens ultimately needs a reason or preconditions to happen.
This statement of yours is not necessarily correct. Some things happen without reason or preconditions. For example: Gravity. Gravity exists without a reason or preconditions.
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