Is atheism a scientific perspective?

[Astreja]

Also, it is not really unreasonable to say that because intelligence is the only known cause, an intelligent agent must have been present to cause it. You want me to provide evidence for a designer without appealing to what we see in nature?

It is extremely unreasonable to assert intelligence as the "only known cause," because we simply do not know that.  We have no evidence whatsoever to connect preexisting organic structures to an intelligent agent that predates modern biotechnology.  You are assuming the existence of an intelligent entity that created life, and using existing life as evidence for the entity.  That is simply not acceptable from a logical point of view.

Here are your choices:

• Independently demonstrate the existence of an entity capable of creating life, then explain how it created life.
  
• Explain the mechanism whereby life originated, then trace that mechanism back to an intelligent agent.
  
• Shrug and say "We don't know... yet."
  

Personally I favour the third option.