Syntax irregularities in Smalltalk

In one aspect, Smalltalk is a very small and elegant language. But I find there are some hidden intricacies when you actually use it. One example is the difference between using the messages whileTrue: and ifTrue:. whileTrue: expects a Block, while ifTrue: expects a Boolean. In the following, at first glance it's not understood why one uses square brackets and the other parenthesis:

[count < 10] whileTrue: [count := count + 1]
(count < 10) ifTrue: [count := count + 1]

Once you understand the semantics of Smalltalk then you comprehend it, but I find this somewhat odd. If Block supported the messages of Boolean, I think the syntax would be more orthogonal:

([x > 0] and: [x < 10]) and: ([y > 0] and: [y < 10])

Compared with the odd amalgamation of []s and ()s:

((x > 0) and: [x < 10]) and: [(y > 0) and: [y < 10]]