## Change Assertion Direction Help

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To change the assertion direction of the displayed assertion, select a new direction (Forward or Backward), then press the [Change Direction] button. The assertion itself is displayed in its EL form at the bottom of the page.

This will delete the assertion from the KB, and reassert it with the new direction. This is better than using the Assert Similar Formula facility, since it is usually undesirable to have the same formula asserted with two different directions at the same time.

There is a third direction, Code, for assertions for which special HL modules have been written to supplant the need for inference using the assertion itself. These assertions are left in the KB for pedagogical and documentation reasons, but are not actually used in inference (outside of the HL modules). Code assertions cannot be edited via the HTML interface, and the ability to make Code assertions is only possible in versions of CYC® with access to the SubL source code.

To restore the setting for assertion direction to its value before editing, press the [Current Value] button.

To abort the edit completely and return to the previous page, press the [Abort Edit] button.

For more information on assertions and assertion directions, see The Syntax of CycL.

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