It puzzles me why you would say that. Stephen Hawking is an agnostic, does that make himn slothful?
S****lothful in a spiritual sense, yes. Make a decision: either God exists, or He does not.
Hawking is one among innumerable brilliant people who are either waiting for some shred of proof/disproof from science (something which is inherently impossible), or refuses to commit to a decision on this greatest of cosmic questions in the interests of remaining purely objective and unbiased. A true scientist! Science and religion are on completely different levels. One deals with the material, the other spiritual; one studies the natural, the other supernatural. One realm (sensible) we can clearly perceive, the other (intelligible) we only know directly in our own minds; its operation and immaterial substance, and indirectly by its effect on the material (which can be sensibly observed).
It is quite simple: the intelligible is observable by the intelligible, and the sensible by the sensible. Since our current intelligible realities (intelligent minds subjected to sensible bodies) are restricted to outside observers who are all in the same way restricted, anything outside of ourselves which is purely intelligible is unobservable. To clarify: we cannot physically see into one another’s minds because our only tool for seeing anything outside of ourselves are our eyes, which are sensible and can only observe other sensible realities; yet we do not assert that our own minds are the only existing intelligible realities. We do not, because of our inability to physically see other minds, say that they do not exist. This is the limitation of scientific observation, which is itself wholly limited to the sensible, the physical, the material.
No amount of arguing about the origins of the universe is going to have even the slightest effect on something that is fundamentally a matter of faith, hence to make the leap we have recourse to reason; to philosophy. Man has been pondering this question since the dawn of his intelligent awakening, and no idea currently held is a completely new one. Some either accept both material and spiritual realms, or they (like Kant) take a purely
spiritualistic view, distrusting all sensible reality as a product of the intelligible mind observing it (there is no physical universe). This errs on the side of illusionism. Atheists completely deny any spiritual reality, adhering to a purely
materialistic world-view, which I can respect, insofar as they are committing to something, despite some of its blatant irrationalities and limitations. All that is sensible (the universe) is filtered through the intelligible (our own minds). To deny the intelligible realities is to deny our
own existence, much less that of God! (see: Descartes’ “Meditations”).
In conclusion, not everything that exists can be perceived by our 5 bodily senses or tools made to enhance them (not everything is sensible). You can never prove the substance of my thoughts or dreams (intelligible realities) purely from scientific observation. You can never prove the intelligible substance of the universe purely from scientific observation; you must either simply accept or deny their existence. Yes, the electricity in my brain is an effect of my thoughts and dreams. Accept or deny that I have thoughts or dreams? The universe is an effect of God. Accept or deny that there is a God? The material effect can be scientifically observed (electricity and universe), the spiritual cause cannot (thoughts and God).
some good reading:
http://www.orestesbrownson.com/conflict.html