I've read a lot of the getting started problems and haven't seen this situation.
I installed FirePHPCore directly in a directory from which I intend to use it. (website on a shared server)
Then, I created a very simple test script:
<?php
require_once('FirePHPCore/FirePHP.class.php');
$firephp = FirePHP::getInstance(true);
FB::log("Firebug ready");
?>
Executing it fetches the following parse error:
Parse error: syntax error, unexpected T_CONST, expecting T_OLD_FUNCTION or T_FUNCTION or T_VAR or '}' in /home/.alla/bobeaston/bob-easton.com/wp_acc/wp-admin/includes/FirePHPCore/FirePHP.class.php on line 65
Yes, I'm a novice php user. I tried many variants of that simple test script, but always came to the same parse error.
TIA, Bob