// Same as above, but for multiple pages (from wpsnipp.com)
// Load CF7 scripts & CSS only on page id's mentioned in array
add_action( 'wp_print_scripts', 'deregister_cf7_javascript', 100 );
function deregister_cf7_javascript() {
    if ( !is_page(array(8,10)) ) {
        wp_deregister_script( 'contact-form-7' );
    }
}
add_action( 'wp_print_styles', 'deregister_cf7_styles', 100 );
function deregister_cf7_styles() {
    if ( !is_page(array(8,10)) ) {
        wp_deregister_style( 'contact-form-7' );
    }
}