Use the boolean compare operators
<? $three = 3; $four = 4; $my_pi = 3.14159; if (($three == $three) and ($four === $four) and ($three != $four) and ($three < $four) and ($three <= $four) and ($four >= $three) and ($three <= $three) and ($my_pi > $three) and ($my_pi <= $four)) print("Yes!<BR>"); else print("No?<BR>"); ?>